Written on 07 January 2018.

Why is the Garonne river so "Dirty"?

Because I hear it too often, I try to answer to one of the recurring questions from my dear guests here in Bordeaux... Why does the Garonne look so "dirty"?

So, first of all, we don't say "dirty"! It might offend us! The exact word is "TURBID". I relay here an article published on Facebook on December 14,2017... It captured one of my favorite bloggers attention : "the English man in Bordeaux" behind the great blog : Invisible Bordeaux.

I relay here an article published on Facebook on December 14,2017 which captured the Tim's Pike attention. He is one of my favorite bloggers,"the English man in Bordeaux" behind the great blog : Invisible Bordeaux. He kindly offered to republish it on his blog.

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“To begin with, it is wrong to say the water is dirty, the exact term is “turbid” (cloudy or opaque). OK, it’s not easy to slip that word into conversations but it could prove useful the next time you play Scrabble! Other ways of describing the colour in French include “limoneuse” (loamy), “blonde” or even “café au lait” (milky coffee)…

And don’t listen to what your fellow passenger on the tram is saying. No, the Garonne has not suddenly turned brown because it rained in the Pyrenees last Saturday! The river is actually brown more or less 365 days per year!

The colour is the end-result of a natural phenomenon. To keep things simple, the fresh water (that flows in the Garonne from its source) is laden with sediment (mainly clay). With the effect of the oceanic tides, the river comes up against an incoming current made of salty seawater.

In chemical terms, the salty water is heavier than the fresh water, resulting in a kind of undercurrent amplified by the riverbanks and which brings the sediment to the surface. This reaction is what gives the Garonne its lovely brown colour.